Hydraulically driven rotor assemblies for rotating working implements secured to the end of articulated booms of handling working vehicles are known. However, a disadvantage of some of these rotor assemblies is that they are bulky, difficult to service as they require the dismantling of many and heavy mechanical parts. Some others have the disadvantage that oil leaks often develop in the collector assembly which couples the pressurized hydraulic fluid to the oil pressure lines which are connected to the working implement to actuate its working parts. These oil pressure lines must be displaced with the rotor assembly, as the working implement is swivelled. These rotor assemblies also are capable of continuous rotation about their main shaft. With most prior art rotor assemblies, because the working implement is connected directly to the rotor assembly, the rotor assembly parts are subjected to torque and/or axial loads and/or radial loads. This imparts stress on the collector and causes the wearing of bearings, seals and couplings and the collector eventually develops hydraulic fluid leaks, thereby necessitating servicing and rehauling. Often, it is required to replace the entire rotor assembly and working implement, thereby rendering the working vehicle, such as a tree-handling machine, idle for several hours or days, and this is a very costly process.
Rotors with rotating load-bearing shafts or orientation crown assembly (i.e., slewing ring) are also known. These rotating shafts may also be equipped with a floating collector. However, a disadvantage of these is that the shaft is less resistant to radial loads than a fixed shaft. Also, an orientation crown assembly has proven to be bothersome due to the fact that its diameter must be large to withstand axial loads.